Xerox 560 Reference Manual page 169

BP STATUS AND NO.
Th i s group of i ndi cators perm i ts the processor address
(usually 0) and current internal state (RUN, WAIT, or
HALT) of the BP to be displayed. While executing in-
structions, the BP is normally in the RUN or WAIT state.
The HALT state is entered only when an address halt occurs,
the processor disable is on (see
II
Operating Procedures and
Information lr
)
or an irrecoverable processor fault occurs.
When the system is in the IDLE state as a result of power
on, a ZCHLT command, or a pc command, only the processor
address is lighted and RUN, WAIT, and HALT indicators
are extinguished.
ALARM AUDIO
This 4-position rotary switch controls the connection and
volume of a loudspeaker, and also permits all indicators
(except POWER ON and PRIMARY POWER) on the SCP to
be tested. When this switch is in the OFF position, the
loudspeaker is disconnected. Note that this switch does
not inhibit the ALARM indicator. When this switch is in
the LOW position, the loudspeaker is connected and the
volume is set to a low level. When this switch is in the
HIGH position, the loudspeaker is connected and the
volume is set to a high level. When this switch is held in
the LAMP TEST position, all back-lighted indicators should
illuminate, simultaneously. The switch returns to the
HIGH position when released.
SCC FUNCTIONS
This sWitch controis the functionai capabiiities of the Sys-
tem Control Console(s). When this switch is in the ENABLE
position, the SCC device(s) may perform the various con-
trol functions attributed to a System Control Console.
Certain control functions require the system to be in the
IDLE state while others (as described under "Maintenance
Control Commands") require the MAINT MODE switch to
be in the ON position.
When the SCC FUNCTIONS switch is in the DISABLE
position, the control functions that may be entered from
the control console (to interact with operating software)
are limited to the following:
1. Operator requested interrupt (Zc I ),
2. Read Sense Switches (ZcSSW),
3. Set Sense Switches (Zc SS #).
The operator may lock out potentially disruptive control
commands when the operating software isrunning by setting
the SCC FUNCTIONS switch to DISABLE.
REMOTE CHANNEL
This 3-position rotary switch controls the manner in which
the alternate and remote consoles may operate. When this
switch is in the SCC position, the alternate and remote
consoles may be connected in parallel with the System
Control Console and may perform the same control func':"
tions as the local control device. The remote console also
requires a manual connection through the RD1 data set.
Note that any restrictions upon the control functions im-
posed upon the local control device by the SCC FUNC-
TIONS switch being in the DISABLE position also apply
to both consoles. Either the alternate or remote console
is selected for input by the AL TSEL switch on the Con-
figuration Control Panel (see Chapter 6).
When the REMOTE CHANNEL switch is in the OFF position,
the remote device is disconnected from the ECS at the data
set (if present). The alternate console functions in the I/o
mode.
When this switch is in the I/o position, the alternate and
remote consoles operate strictly as I/O devices communi-
cating with the computer system via lOP subchannel address
X'OB'. Only one device is selected for input at a time by
the ALTSEL switch on the Configuration Control Panel
(see Chapter 6).
MAINT MODE
During normal operations, this switch is placed in the OFF
position. During maintenance and/or diagnostic activies,
this switch may be placed in the ON position or momentar-
i Iy held in the RESET position (switch automatically returns
to the ON position when released). In addition to causing
the MAINTENANCE MODE indicator to become illumi-
nated when piaced in the ON position, the sWitch aiso en-
ables certain hardware controls and allows their associated
control commands to be entered from the operator's control
console (see "Maintenance Control Commands"). This
interlocking feature prevents inadvertent adverse effects
upon the current program.
Caution should be exercised in activating RESET, since
this position (equivalent to the SCC SUPER RESET com-
mand) causes all components of the system to be reset and
initialized.
SELECT DISPLAY
These nine switches, labeled CCP/SCSR and 0 through 7,
are used to specify the binary address of anyone of up to
256 Single Clock Status Registers and up to 32 Configura-
tion Status Registers or Read Direct Mode 9 Status Reg-
isters whose content is to be displayed by the 32 binary
indicators, labeled 0 through 31.
When the CCP/SCSR switch is in the SCSR position,
switches 0 through 3 specify the cluster address and
switches 4 through 7 specify the element address of the
Single Clock Status Register whose content is to be
displayed.
Control Commands 163